EJB Components 

The applications enterprise beans are packed in JAR file(s), which are packed in the EAR file and deployed on J2EE Engine 7.0. The JAR file must consist of:

●      All the beans’ classes and interfaces

●      ejb-jar.xml, which must be J2EE 1.2 or 1.3 compliant

●      ejb-j2ee-engine.xml – a J2EE Engine-specific deployment descriptor that contains specific deployment settings

●      persistent.xml – a J2EE Engine-specific deployment descriptor, which is necessary only if your EJB application contains container-managed entity beans

The deployment descriptors are located in a META-INF directory in the JAR file.

The EJB applications that run on J2EE Engine 6.20 are compatible with the J2EE 1.2 standards (Enterprise JavaBeans Specification 1.1). They do not have ejb-j2ee-engine.xml and instead of persistent.xml for container-managed entity beans, they contain storage.xml. If your EJB application contains additional deployment properties, they are specified in the standard ejb-jar.xml.

Use the SAP NetWeaver Developer Studio or the Deploy Tool to redeploy your EJB application on the J2EE Engine 7.0. You can also use the GENERATE_PERSISTENT shell command from the EJB group of shell commands to generate persistent.xml for your container-managed entity beans. This process does not differ from the process of generating persistent.xml with the Converter Tool or the Deploy Tool.

You do not have to redeploy each component of your application. When you redeploy or convert the application’s EAR file, the converter will automatically convert the deployment descriptors in the application’s JAR files as described below.

Using the SAP NetWeaver Developer Studio

If you use the SAP NetWeaver Developer Studio to assemble your EJB application and to deploy it on the J2EE Engine 7.0, the SAP NetWeaver Developer Studio will create the necessary J2EE compliant deployment descriptors, compose an SDA file, and will also deploy the application through the SDM.

Using the Deploy Tool

If your EJB application contains specific settings in ejb-jar.xml, then the converter will replace the existing ejb-jar.xml with an EJB 1.1 compatible ejb-jar.xml, and will create the ejb-j2ee-engine.xml in which it will store the additional deployment properties. If the EJB application does not contain specific deployment properties and container-managed entity beans, the EJB application will be deployed as is, that is, the converter will not modify the existing ejb-jar.xml.

When you redeploy an EJB application containing container-managed entity beans, the system will display a warning message that storage.xml exists, and will use the information from storage.xml to create persistent.xml. The storage.xml deployment descriptor will not be removed but the J2EE Engine 7.0 will use the newly generated persistent.xml.

If the system converts storage.xml into persistent.xml and you do not specify the name of the data source that your application will use, the system will choose a random DBPool name from storage.xml and will set it as data source in persistent.xml. If the data source is not specified in storage.xml, the system will throw an exception.

For more information, see Generating persistent.xml for Container-Managed Entity Beans (in the Administration Manual).

For information about the main incompatible changes in the EJB Container between J2EE Engine 6.20 and 7.0, and how to solve any possible problems arising from these changes, see EJB Container.

 

See also:

Developing Enterprise Beans (in the Development Manual)